Hammerstorm

Gameplay features and bonuses

Hammerstorm is set on a standard 5×3 grid with 40 paylines, though the layout can expand during gameplay. The slot offers high volatility and an RTP rate of 96.50%.

Wild Symbol: The Wild can appear on all reels and substitutes for all symbols except Red, Green, Purple, Silver, Gold Lightning, Silver Coin, Gold Coin, and Thor symbols.

Lightning Symbols & Modifier Collection: During the base game, Red, Green, and Purple Lightning symbols may appear. When they land, they are collected into their matching modifier chests — Double, Expand, or Spins — shown above the reels. At the end of any spin, collecting one or more of these symbols may randomly trigger the Respins Feature, activating one, two, or all three modifiers.

Each Lightning symbol also acts as a Money symbol with a random value from this set:
0.5x, 1x, 1.5x, 2x, 2.5x, 3x, 4x, 5x, 6x, 8x, 10x, 12x, 12.5x, 20x, 37.5x, 40x, 50x, 100x, 250x, 625x, or 10,000x the total bet.

Thor Symbol: This symbol lands only on reel 1. If it hits with at least one Lightning symbol elsewhere on the reels, the Respins Feature triggers automatically.

Respins Feature

When activated, the round is played on a 5×5 grid containing only blank spaces and Coin or Lightning Money symbols. A marked collection zone, starting at 2×2, shifts to different spots between Respins. At the start, all triggering Lightning symbol values are collected into this zone.

When Coin or Lightning Money symbols land inside the marked area, their values are collected. Each Lightning Money symbol also fills a meter. Collecting enough symbols expands the collection zone and adds more Respins:

• 5 collected: Expands to 3×3 and awards 3 Respins.
• 4 collected: Expands to 4×4 and awards 2 Respins.
• 3 collected: Expands to 5×5 and awards 1 Respin.

Extra symbol values during the feature include 0.5x to 10,000x total bet, or +1 Spin when the Spins modifier is active. Silver and Gold Coin or Lightning symbols appear only during Respins, and Gold versions appear only if the Double modifier is active.

Modifiers

Double: Gold Coin and Lightning symbols may appear. When collected, their value is awarded twice: first using the original number, then using a new random one.

Expand: The grid grows to 7×7. The collection zone can grow from 5×5 to 6×5, 6×6, and 7×6. Each expansion takes 3 Lightning symbols and adds 3, 3, 3, 2, or 1 Respins depending on the upgrade level.

Spins: +1 Spin may appear on Lightning symbols. Collecting it adds an extra Respin.

Ante Bet Options

• Ante Bet 1 (500x bet multiplier): Guarantees 1 Thor symbol lands on reel 1 every spin.
• Ante Bet 2 (1,000x bet multiplier): Guarantees at least 5 Lightning Money symbols land randomly on the grid during every spin.

Design and Soundtrack

Hammerstorm immerses players in a Viking mythology-inspired world, set against the backdrop of a mountainous village landscape. The scene includes small wooden houses, a dock, and a distant castle in the background, which creates a rich and atmospheric setting. In addition, the reels feature classic J–A figures, alongside thematic symbols such as horns, gloves, helmets, axes, and shields. The overall experience is further enhanced by a fitting soundtrack that complements the game's Norse theme.

For players interested in similar Viking-themed slots, Viking Runecraft 100 by Play’n GO and Viking Forge by Pragmatic Play are strong alternatives to consider.

The Bottom Line

Hammerstorm offers a dynamic gameplay experience packed with engaging features, including a Respin round with three possible modifiers that can trigger individually or in combination. The use of Money symbols with values up to 10,000x adds high win potential, especially during the expanding 5×5 or 7×7 grids. Additionally, with mechanics like Ante Bets and a unique collection zone system, the slot provides variety and depth across spins.